The present invention relates to cable products and, more particularly, to coiled cable products and methods for forming the same.
An extensive infrastructure supporting telecommunication has been developed, traditionally based upon copper wire connections between individual subscribers and telecommunications company network distribution points. More recently, much of the telecommunications network infrastructure is being extended or replaced with an optical fiber based communications network infrastructure. The carrying capacity and communication rate capabilities of such equipment may exceed that provided by conventional copper wired systems.
As such, fiber optic cables are widely used for telecommunications applications where high information capacity, noise immunity and other advantages of optical fibers may be exploited. Fiber cable architectures are emerging for connecting homes and/or business establishments, via optical fibers, to a central location, for example. A trunk or main cable may be routed, for example, through a housing subdivision and small fiber count “drop cables” may be spliced to the main cable at predetermined spaced apart locations.
Typical flat drop style fiber optic cable is stiff, springy, and has an oval cross section (not round). In particular, it generally resists twisting around its axis. This may make such cables very difficult to handle. Unlike some round cross section cables, if flat cable is forced into a twist about it's axis, it tends to bow up into a helical spring shape, and can tangle easily. As used herein, a “springy” or “resilient” cable refers to a cable, such as a flat drop style fiber optic cable, that has an inherent tendency to expand outwards when coiled while a “stiff” cable refers to a cable that is resistant to bending like a springy or resilient cable but does not have an inherent tendency to expand outwards. Thus, for example, a typical maritime rope is neither springy nor stiff.
This twisting can be a problem when a springy cable is being unwound from a conventional reel. Particular care may be needed to control the drag on the reel so that the outer loops do not spring out to a larger diameter than the outside of the reel and fall off the reel and/or become tangled with one another. This is typically done with complex de-reeling machines with drag brakes or by having a person dedicated to manually tending the reel as it is unwound.
Optical fibers in an optical fiber cable are also sensitive to twist that can be imparted when removing the cable from a spool or the like. In particular, accumulated twist generally is not good for cables, and fiber cable particularly. When unwinding from a conventional reel, the reel generally must be able to rotate like a wheel. Otherwise, accumulated twist may be imparted to fiber as the cable is unwound by pulling it along the central axis of the reel off an end of the cable reel. Thus, additional equipment may be needed during field installation of cable to allow the cable reels to rotate during drawing of the cable.